The FIRST H&R shotgun chambered for 2 3/4" cartridges was the upgraded Model 1908 - Variation 2 - which was introduced in 1921 or '22. Up to that date/year - all the older H&Rs were chambered for 2 1/2" 12 ga.
This variation will have a "long", slim fore stock. The 1st picture is a 1st Variation. The second picture is a later variation with 2 3/4" chamber.
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